Students can Download Chapter 15 Air Around Us Questions and Answers, Notes Pdf, KSEEB Solutions for Class 6 Science, Karnataka State Board Solutions help you to revise complete Syllabus and score more marks in your examinations.

Karnataka State Syllabus Class 6 Science Chapter 15 Air Around Us

Class 6 Science Air Around Us NCERT Textbook Questions and Answers

Question 1.
What is the composition of air?
Answer:
Air contains some gases mainly nitrogen, oxygen, small amount of carbon dioxide, water vapour and dust particles

Question 2.
Which gas in the atmosphere is essential for respiration?
Answer:
Oxygen gas in the atmosphere is essential for respiration.

Question 3.
How will you prove that air support burning?
Answer:
Step 1: Two shallow containers are taken and burning candles are fitted into it.
step 2: Now, water is filled in the container at two different levels.
Step 3: Both the candles are then covered with glass.
Step 4: After sometime, we observe that the candles having less water in its container stops burning.
This happened because the container having more water contains more oxygen and therefore it bums for more time, Thus, it is proved that air support burning.

Question 4.
How will you show that air is dissolved in water?
Answer:
Steps 1: Water is taken in a pan.
Steps 2: It is now boiled on a stove
Steps 3: We will observe tiny visible bubbles of water visible, coming out from the bottom of the pan. These tiny bubbles are coming due to the air dissolved in water Thus this proves that air is dissolved in water.

Question 5.
Why does a lump of cotton wool shrink in water?
Answer:
The lump of cotton contains air in it, when it comes in contact with water, the air is pushed out from the vacant space and dissolved in water and thus a lump of cotton wool, shrinks in water.

Question 6.
The layer of air around the earth is known as ___
Answer:
Atmosphere

Question 7.
The component of air used by green plant to make their food is ___
Answer:
Carbon dioxide

Question 8.
List five activities that are possible due to the presence of air
Answer:
a) Helps in seed dispersal and pollination
b) Sailing of ships
c) Flying of the birds and kites
d) Gives us oxygen to respire
e) Moving air helps in the rotation of wind mill

Question 9.
How do plants and animals help each other in the exchange of gases in the atmosphere?
Answer:
Plants take in CO2 in during photosynthesis and give out oxygen into the atmosphere, while animals take in oxygen and breathe out carbon dioxide during respiration, In this way, plants and animals help each other in the exchange of gases in the atmosphere.

Class 6 Science Air Around Us Additional Important Questions and Answers

I. Choose the correct answer:

Question 1.
The blanket of gases that surround the earth is called ___
a) Air
b) Atmosphere
c) Lithosphere
d) Biosphere
Answer:
b) Atmosphere

Question 2.
Which one of the following has the major part of air?
a) Nitrogen
b) Oxygen
c) Carbondioxide
d) Helium
Answer:
a) Nitrogen

Question 3.
Identify the gas “Odourless, colourless, heavier than air, supports combustion”
a) Nitrogen
b) Oxygen
c) Carbondioxide
d) Water vapour
Answer:
b) Oxygen

Question 4.
Which one of the following statement is true?
a) ‘Air is opaque’
b) Air is made of one substance only
c) Air contains water vapour
d) Air contains large amount of inert gases.
Answer:
c) Air contains water vapour

Question 5.
Which gas is produced by plant during photosynthesis?
a) Nitrogen
b) Carbondioxide
c) Hydrogen
d) Oxygen
Answer:
d) Oxygen

Question 6.
A gas is colourless, odurless, heavier, then air and extinguishes fire, name the gas
a) Nitrogen
b) Carbondioxide
c) Hydrogen
d) Oxygen
Answer:
b) Carbondioxide

Question 7.
Which gas present in atmosphere allows substance to burn
a) Nitrogen
b) Carbondioxide
c) Oxygen
d) Ozone
Answer:
c) Oxygen

Question 8.
Clothes dry faster when there is ___ water vapour in air
a) Less
b) More
c) Either less or more
d) None of these
Answer:
a) Less

Question 9.
Hot air balloon rises up in the air because?
a. Hot air is heavier than cold air
b. Hot air is lighter than cold air
c. Hot air does not play any role in rising up the balloon
d. Hot air contains water vapour which push up the balloon
Answer:
c. Hot air does not play any role in rising up the balloon

Question 10.
Removal of water from plant bodies in the form of vapours is called
a) Photosynthesis
b) Respiration
c) Transpiration
d) Condensation
Answer:
c) Transpiration

II. Answer the following question:

Question 1.
What is the percentage of nitrogen and oxygen in air?
Answer:
Nitrogen – 78.1% Oxygen – 20.9%

Question 2.
What are the sources of carbondioxide in air?
Answer:
Respiration by animals and plants and burning of fuel

Question 3.
Why is air considered as a mixture?
Answer:
Air contains oxygen and nitrogen as its major constituents of air, These gases retain their properties in air So air is called a mixture

Question 4.
What is wind energy? Mention its two advantage
Answer:
Blowing air is called wind. Wind possesses kinetic energy The kinetic energy Possessed by wind is called wind energy Uses of wind energy are;

  1. Wind energy is used to pump the ground water
  2. Wind energy is used to generate electricity with the help of wind mills

Question 5.
Mention two uses of air
Answer:
a) For respiration all organisms need air
b) For burning of any substance air is needed

Question 6.
What happens if the percentage of oxygen in the air reaches 70%?
Answer:
If any substance catches fire it will become difficult to extinguish the fire, oxygen supports combustion.

Question 7.
How will you prove the soil contains air in it?
Answer:
Take a glass tumbler add some soil in it, then pour some water on the soil slowly, the air – bubbles comes out of the soil. This proves that soil holds air in it

Question 8.
Explain why mountaineers carry oxygen cylinders with them?
Answer:
As you go up, above the sea – level the atmospheric pressure goes on decreasing and the amount of oxygen also decreases at higher attitude. Hence moutaineers carry oxygen cylinders with them

Question 9.
What is air? Name major constituents of air. Also give their volume proportions in air.
Answer:
Air is a mixture of gases, The major constituents of air are nitrogen, oxygen, carbondioxide, and argon, The percentage composition of constituents of air are as given below consult author for percentage of components of air. Other components of air are water vapour and dust particles.

Question 10.
Air is a mixture prove this statement
Answer:
The components of mixture can be easily separated and they retain their properties. The components of air are: Oxygen, nitrogen water vapour and carbondioxide, all these gases can be easily separated and they retain their properties.

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